Finish redaction algorithm.

synapse/api/events/__init__.py

@@ -86,8 +86,8 @@ class SynapseEvent(JsonEncodedObject):
 
     def __init__(self, raises=True, **kwargs):
         super(SynapseEvent, self).__init__(**kwargs)
-        if "content" in kwargs:
-            self.check_json(self.content, raises=raises)
+        # if "content" in kwargs:
+        #     self.check_json(self.content, raises=raises)
 
     def get_content_template(self):
         """ Retrieve the JSON template for this event as a dict.

synapse/api/events/utils.py

@@ -18,24 +18,31 @@ from .room import (
     RoomAliasesEvent, RoomCreateEvent,
 )
 
+
 def prune_event(event):
-    """ Prunes the given event of all keys we don't know about or think could
-    potentially be dodgy.
+    """ Returns a pruned version of the given event, which removes all keys we
+    don't know about or think could potentially be dodgy.
 
     This is used when we "redact" an event. We want to remove all fields that
     the user has specified, but we do want to keep necessary information like
     type, state_key etc.
     """
-    return _prune_event_or_pdu(event.type, event)
+    event_type = event.type
 
-def prune_pdu(pdu):
-    """Removes keys that contain unrestricted and non-essential data from a PDU
-    """
-    return _prune_event_or_pdu(pdu.type, pdu)
-
-def _prune_event_or_pdu(event_type, event):
-    # Remove all extraneous fields.
-    event.unrecognized_keys = {}
+    allowed_keys = [
+        "event_id",
+        "user_id",
+        "room_id",
+        "hashes",
+        "signatures",
+        "content",
+        "type",
+        "state_key",
+        "depth",
+        "prev_events",
+        "prev_state",
+        "auth_events",
+    ]
 
     new_content = {}
 
@@ -65,6 +72,12 @@ def _prune_event_or_pdu(event_type, event):
     elif event_type == RoomAliasesEvent.TYPE:
         add_fields("aliases")
 
-    event.content = new_content
+    allowed_fields = {
+        k: v
+        for k, v in event.get_full_dict().items()
+        if k in allowed_keys
+    }
 
-    return event
+    allowed_fields["content"] = new_content
+
+    return type(event)(**allowed_fields)

synapse/crypto/event_signing.py

@@ -55,9 +55,7 @@ def _compute_content_hash(event, hash_algorithm):
 
 
 def compute_event_reference_hash(event, hash_algorithm=hashlib.sha256):
-    # FIXME(erikj): GenericEvent!
-    tmp_event = GenericEvent(**event.get_full_dict())
-    tmp_event = prune_event(tmp_event)
+    tmp_event = prune_event(event)
     event_json = tmp_event.get_dict()
     event_json.pop("signatures", None)
     event_json.pop("age_ts", None)
@@ -68,8 +66,7 @@ def compute_event_reference_hash(event, hash_algorithm=hashlib.sha256):
 
 
 def compute_event_signature(event, signature_name, signing_key):
-    tmp_event = copy.deepcopy(event)
-    tmp_event = prune_event(tmp_event)
+    tmp_event = prune_event(event)
     redact_json = tmp_event.get_full_dict()
     redact_json.pop("signatures", None)
     redact_json.pop("age_ts", None)

synapse/federation/units.py

@@ -56,17 +56,15 @@ class Pdu(JsonEncodedObject):
         "origin_server_ts",
         "type",
         "destinations",
-        "transaction_id",
         "prev_events",
         "depth",
         "content",
-        "outlier",
         "hashes",
+        "user_id",
+        "auth_events",
         "signatures",  # Below this are keys valid only for State Pdus.
         "state_key",
         "prev_state",
-        "required_power_level",
-        "user_id",
     ]
 
     internal_keys = [

synapse/storage/_base.py

@@ -509,7 +509,7 @@ class SQLBaseStore(object):
                 )
 
                 if del_evs:
-                    prune_event(ev)
+                    ev = prune_event(ev)
                     ev.redacted_because = del_evs[0]
 
         return events